Some Medical and other Aspects of Bacterial Chemistry: (Section of Pathology)

The evolution of bacterial chemistry as applied to medicine from bacterial chemistry as applied for economic purposes is traced. The outlook of the bacterial chemist is contrasted with that of the medical bacteriologist.The possible results of the study of bacterial nutrition from the medical aspect are noted. Difficulties arise from the fact that the nutrition of a single species varies. A variation in bacterial enzymes results from alteration in the substrate.The evolution of bacteria from primitive autotrophic types to the parasitic types of the present day may be explained on the basis of an evolution depending upon a gradual alteration in the substrate. The primitive bacteria in an evolutionary sense are endowed with great powers of synthesis, while the evolved bacteria are not. Thus, while the primitive bacteria can synthesize their protoplasm from simple nutrients, the parasitic bacteria cannot and must receive complex compounds pre-formed.In the case of parasitic bacteria this taking of nutrients from the tissue cells may have a bearing upon disease. An infective disease may in part be a deficiency disease. An essential cell nutrient may be taken from the cells by the bacteria, with a result that they cannot function properly in the "anti" sense.